libxl: introduce libxl_node_to_cpumap

As an helper for the special case (of libxl_nodemap_to_cpumap) when
one wants the cpumap for just one node.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

2 files changed, 25 insertions, 0 deletions

diff --git a/tools/libxl/libxl_utils.c b/tools/libxl/libxl_utils.c
index 244725bd7f..1bcac7e2f7 100644
--- a/tools/libxl/libxl_utils.c
+++ b/tools/libxl/libxl_utils.c
@@ -668,6 +668,28 @@ int libxl_nodemap_to_cpumap(libxl_ctx *ctx,
     return rc;
 }
 
+int libxl_node_to_cpumap(libxl_ctx *ctx, int node,
+                         libxl_bitmap *cpumap)
+{
+    libxl_bitmap nodemap;
+    int rc = 0;
+
+    libxl_bitmap_init(&nodemap);
+
+    rc = libxl_node_bitmap_alloc(ctx, &nodemap, 0);
+    if (rc)
+        goto out;
+
+    libxl_bitmap_set_none(&nodemap);
+    libxl_bitmap_set(&nodemap, node);
+
+    rc = libxl_nodemap_to_cpumap(ctx, &nodemap, cpumap);
+
+ out:
+    libxl_bitmap_dispose(&nodemap);
+    return rc;
+}
+
 int libxl_cpumap_to_nodemap(libxl_ctx *ctx,
                             const libxl_bitmap *cpumap,
                             libxl_bitmap *nodemap)
diff --git a/tools/libxl/libxl_utils.h b/tools/libxl/libxl_utils.h
index a430362fe5..7b84e6a0a4 100644
--- a/tools/libxl/libxl_utils.h
+++ b/tools/libxl/libxl_utils.h
@@ -129,6 +129,9 @@ static inline int libxl_node_bitmap_alloc(libxl_ctx *ctx,
 int libxl_nodemap_to_cpumap(libxl_ctx *ctx,
                             const libxl_bitmap *nodemap,
                             libxl_bitmap *cpumap);
+/* Populate cpumap with the cpus spanned by node */
+int libxl_node_to_cpumap(libxl_ctx *ctx, int node,
+                         libxl_bitmap *cpumap);
 /* Populate nodemap with the nodes of the cpus in cpumap */
 int libxl_cpumap_to_nodemap(libxl_ctx *ctx,
                             const libxl_bitmap *cpuemap,